Much of Odum Library's maps collection comes from the U.S. Federal Government, the largest source for research and publishing of maps in the United States.
Federal agencies that publish maps include
Superintendent of Documents--more commonly known as SuDoc--numbers make up the classification system used for federal government documents.
SuDocs are based on the federal agency that publishes the document (rather than a subject classification):
For example, in Sudoc number C3.186/2:983
For more information on reading SuDocs numbers, see our guide to Shelving Sudocs.